The present invention is an improvement upon the fibre optic light source device disclosed in Canadian Patent No. 980,312, corresponding to U.S. Pat. No. 3,831,017, which is concerned with apparatus for selectively illuminating the receptor end faces of fibre optic cables supplied by different manufacturers.
Canadian Patent No. 980,312 teaches a light source device having a lamp support means for presenting a lamp or incandescent bulb as the source of illumination, and a movable selector, which in the preferred embodiment is a circular rotatable turret supporting the receptacles at different angular positions on an arc which intercepts the lamp lens. Such movable selector-turret is positioned at the lens end of the lamp, and at least a pair of receptacles are mounted on such selector, each receptacle having an aperture therein for receiving the receptor end of a fibre optic cable and being alignable with the lamp upon movement of the selector. The receptacles are each of different configuration to enable respectively different cable receptors to be fitted thereto.
As a further refinement, Canadian Patent No. 980,312 contemplates use of a light concentrating means in the form of a concave reflector element 12 for providing a concentrated point source of light focused on the receptor ends of the fibre optic cables, as shown in FIGS. 3,4, and 5 thereof. The reflector has the effect of being able to direct most of the emitted light to the receptor end of the fibre optic cable, thereby increasing the intensity and brilliance of the light available from the fibre optic cable.
Means by which light may be concentrated are well known in the art, and include, as disclosed in Canadian Patent No. 980,312, providing a concave reflector positioned behind the lamp or incandescent bulb, to reflect the light towards the apertures in which the receptor ends of the fibre optic cables are received. The concave reflector may also be an integral part of the lamp or incandescent bulb itself, wherein the interior concave side of the bulb opposite the apertures in the receptacles is coated with a highly reflective substance.
Convex lens means may also be incorporated for concentrating the light from the light source on the fibre optic cable receptor ends.
A problem which manifested itself in the design of Canadian Patent No. 980,312, was that because the fibre optic cables and their corresponding receptor ends were usually of different manufacture, not all would have their receptor ends aligned in a common plane when they are located in the receptacle on the movable selector-turret of the light source device. Accordingly, when a light concentrating means was employed, this meant that while the receptor ends of some fibre optic cables would optimally be in a position wherein the light emitted from the light source was concentrated on a point exactly on the receptor end, other receptor ends of cables of different manufacture would be axially displaced either towards, or away from, the light source, with the result that the concentrated point source of light would not be focused at the receptor end. In this instance there would result a loss of intensity of light available to the particular fibre optic cable.